Rewrote the FlowEngine (#256)

* Removed unused components. Updated tests.

Improved checkpointing model

Improved model, started with SimPowerSource

implemented FailureModels and Checkpointing

First working version

midway commit

first update

All simulation are now run with a single CPU and single MemoryUnit. multi CPUs are combined into one. This is for performance and explainability.

* fixed merge conflicts

* Updated M3SA paths.

* Fixed small typo

17 files changed, 0 insertions, 1295 deletions

diff --git a/opendc-faas/opendc-faas-service/build.gradle.kts b/opendc-faas/opendc-faas-service/build.gradle.kts
deleted file mode 100644
index 90cb8f56..00000000
--- a/opendc-faas/opendc-faas-service/build.gradle.kts
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-description = "FaaS service for OpenDC"
-
-// Build configuration
-plugins {
-    `kotlin-library-conventions`
-}
-
-dependencies {
-    api(projects.opendcFaas.opendcFaasApi)
-    api(libs.commons.math3)
-    implementation(projects.opendcCommon)
-    implementation(libs.kotlin.logging)
-
-    testImplementation(projects.opendcSimulator.opendcSimulatorCore)
-    testRuntimeOnly(libs.log4j.core)
-    testRuntimeOnly(libs.log4j.slf4j)
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/FaaSService.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/FaaSService.kt
deleted file mode 100644
index e9634ccc..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/FaaSService.kt
+++ /dev/null
@@ -1,80 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service
-
-import org.opendc.common.Dispatcher
-import org.opendc.faas.api.FaaSClient
-import org.opendc.faas.api.FaaSFunction
-import org.opendc.faas.service.autoscaler.FunctionTerminationPolicy
-import org.opendc.faas.service.deployer.FunctionDeployer
-import org.opendc.faas.service.internal.FaaSServiceImpl
-import org.opendc.faas.service.router.RoutingPolicy
-import org.opendc.faas.service.telemetry.FunctionStats
-import org.opendc.faas.service.telemetry.SchedulerStats
-import java.time.Duration
-
-/**
- * The [FaaSService] hosts the service implementation of the OpenDC FaaS platform.
- */
-public interface FaaSService : AutoCloseable {
-    /**
-     * Create a new [FaaSClient] to control the compute service.
-     */
-    public fun newClient(): FaaSClient
-
-    /**
-     * Collect statistics about the scheduler of the service.
-     */
-    public fun getSchedulerStats(): SchedulerStats
-
-    /**
-     * Collect statistics about the specified [function].
-     */
-    public fun getFunctionStats(function: FaaSFunction): FunctionStats
-
-    /**
-     * Terminate the lifecycle of the FaaS service, stopping all running function instances.
-     */
-    public override fun close()
-
-    public companion object {
-        /**
-         * Construct a new [FaaSService] implementation.
-         *
-         * @param dispatcher The [Dispatcher] used for scheduling events.
-         * @param deployer the [FunctionDeployer] to use for deploying function instances.
-         * @param routingPolicy The policy to route function invocations.
-         * @param terminationPolicy The policy for terminating function instances.
-         * @param quantum The scheduling quantum of the service (100 ms default)
-         */
-        public operator fun invoke(
-            dispatcher: Dispatcher,
-            deployer: FunctionDeployer,
-            routingPolicy: RoutingPolicy,
-            terminationPolicy: FunctionTerminationPolicy,
-            quantum: Duration = Duration.ofMillis(100),
-        ): FaaSService {
-            return FaaSServiceImpl(dispatcher, deployer, routingPolicy, terminationPolicy, quantum)
-        }
-    }
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/FunctionObject.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/FunctionObject.kt
deleted file mode 100644
index 0ed96b96..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/FunctionObject.kt
+++ /dev/null
@@ -1,145 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service
-
-import org.apache.commons.math3.stat.descriptive.DescriptiveStatistics
-import org.opendc.faas.service.deployer.FunctionInstance
-import org.opendc.faas.service.telemetry.FunctionStats
-import java.util.UUID
-
-/**
- * An [FunctionObject] represents the service's view of a serverless function.
- */
-public class FunctionObject(
-    public val uid: UUID,
-    name: String,
-    allocatedMemory: Long,
-    labels: Map<String, String>,
-    meta: Map<String, Any>,
-) : AutoCloseable {
-    /**
-     * Metrics tracked per function.
-     */
-    private var localInvocations = 0L
-    private var localTimelyInvocations = 0L
-    private var localDelayedInvocations = 0L
-    private var localFailedInvocations = 0L
-    private var localActiveInstances = 0
-    private var localIdleInstances = 0
-    private val localWaitTime =
-        DescriptiveStatistics()
-            .apply { windowSize = 100 }
-    private val localActiveTime =
-        DescriptiveStatistics()
-            .apply { windowSize = 100 }
-
-    /**
-     * The instances associated with this function.
-     */
-    public val instances: MutableList<FunctionInstance> = mutableListOf()
-
-    public var name: String = name
-        private set
-
-    public var memorySize: Long = allocatedMemory
-        private set
-
-    public val labels: MutableMap<String, String> = labels.toMutableMap()
-
-    public val meta: MutableMap<String, Any> = meta.toMutableMap()
-
-    /**
-     * Report a scheduled invocation.
-     */
-    internal fun reportSubmission() {
-        localInvocations++
-    }
-
-    /**
-     * Report the deployment of an invocation.
-     */
-    internal fun reportDeployment(isDelayed: Boolean) {
-        if (isDelayed) {
-            localDelayedInvocations++
-            localIdleInstances++
-        } else {
-            localTimelyInvocations++
-        }
-    }
-
-    /**
-     * Report the start of a function invocation.
-     */
-    internal fun reportStart(
-        start: Long,
-        submitTime: Long,
-    ) {
-        val wait = start - submitTime
-        localWaitTime.addValue(wait.toDouble())
-
-        localIdleInstances--
-        localActiveInstances++
-    }
-
-    /**
-     * Report the failure of a function invocation.
-     */
-    internal fun reportFailure() {
-        localFailedInvocations++
-    }
-
-    /**
-     * Report the end of a function invocation.
-     */
-    internal fun reportEnd(duration: Long) {
-        localActiveTime.addValue(duration.toDouble())
-        localIdleInstances++
-        localActiveInstances--
-    }
-
-    /**
-     * Collect the statistics of this function.
-     */
-    internal fun getStats(): FunctionStats {
-        return FunctionStats(
-            localInvocations,
-            localTimelyInvocations,
-            localDelayedInvocations,
-            localFailedInvocations,
-            localActiveInstances,
-            localIdleInstances,
-            localWaitTime.copy(),
-            localActiveTime.copy(),
-        )
-    }
-
-    override fun close() {
-        val copy = instances.toList() // Make copy to prevent concurrent modification
-        copy.forEach(FunctionInstance::close)
-        instances.clear()
-    }
-
-    override fun equals(other: Any?): Boolean = other is FunctionObject && uid == other.uid
-
-    override fun hashCode(): Int = uid.hashCode()
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicy.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicy.kt
deleted file mode 100644
index 2ab3638b..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicy.kt
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.autoscaler
-
-import org.opendc.faas.service.deployer.FunctionInstance
-import org.opendc.faas.service.deployer.FunctionInstanceListener
-
-/**
- * A management policy that is responsible for downscaling the active function instances for a function.
- */
-public interface FunctionTerminationPolicy : FunctionInstanceListener {
-    /**
-     * Enqueue the specified [instance] to be scheduled for termination a
-     */
-    public fun enqueue(instance: FunctionInstance)
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicyFixed.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicyFixed.kt
deleted file mode 100644
index 9edb8c1d..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicyFixed.kt
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.autoscaler
-
-import org.opendc.common.Dispatcher
-import org.opendc.common.util.TimerScheduler
-import org.opendc.faas.service.deployer.FunctionInstance
-import org.opendc.faas.service.deployer.FunctionInstanceState
-import java.time.Duration
-
-/**
- * A [FunctionTerminationPolicy] that terminates idle function instances after a fixed keep-alive time.
- *
- * @param timeout The idle timeout after which the function instance is terminated.
- */
-public class FunctionTerminationPolicyFixed(
-    dispatcher: Dispatcher,
-    public val timeout: Duration,
-) : FunctionTerminationPolicy {
-    /**
-     * The [TimerScheduler] used to schedule the function terminations.
-     */
-    private val scheduler = TimerScheduler<FunctionInstance>(dispatcher)
-
-    override fun enqueue(instance: FunctionInstance) {
-        // Cancel the existing timeout timer
-        scheduler.cancel(instance)
-    }
-
-    override fun onStateChanged(
-        instance: FunctionInstance,
-        newState: FunctionInstanceState,
-    ) {
-        when (newState) {
-            FunctionInstanceState.Active -> scheduler.cancel(instance)
-            FunctionInstanceState.Idle -> schedule(instance)
-            else -> {}
-        }
-    }
-
-    /**
-     * Schedule termination for the specified [instance].
-     */
-    private fun schedule(instance: FunctionInstance) {
-        scheduler.startSingleTimer(instance, timeout.toMillis()) { instance.close() }
-    }
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicyNull.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicyNull.kt
deleted file mode 100644
index 957e569b..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/autoscaler/FunctionTerminationPolicyNull.kt
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.autoscaler
-
-import org.opendc.faas.service.deployer.FunctionInstance
-
-/**
- * A [FunctionTerminationPolicy] that never terminates function instances.
- */
-public class FunctionTerminationPolicyNull : FunctionTerminationPolicy {
-    override fun enqueue(instance: FunctionInstance) {
-        // No-op
-    }
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionDeployer.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionDeployer.kt
deleted file mode 100644
index 13d48fbf..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionDeployer.kt
+++ /dev/null
@@ -1,46 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.deployer
-
-import org.opendc.faas.service.FunctionObject
-
-/**
- * A [FunctionDeployer] is responsible for ensuring that an instance of an arbitrary function, a [FunctionInstance],
- * is deployed.
- *
- * The function deployer should combine the configuration stored in the function registry, the parameters supplied by
- * the requester, and other factors into a decision of how the function should be deployed, including how many and
- * what kind of resources it should receive.
- *
- * Though it decides how the function instance should be deployed, the deployment of the function instance itself is
- * delegated to the Resource Orchestration Layer.
- */
-public interface FunctionDeployer {
-    /**
-     * Deploy the specified [function].
-     */
-    public fun deploy(
-        function: FunctionObject,
-        listener: FunctionInstanceListener,
-    ): FunctionInstance
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstance.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstance.kt
deleted file mode 100644
index 77eadbbe..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstance.kt
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.deployer
-
-import org.opendc.faas.service.FunctionObject
-
-/**
- * A [FunctionInstance] is a self-contained worker—typically a container—capable of handling function executions.
- *
- * Multiple, concurrent function instances can exist for a single function, for scalability purposes.
- */
-public interface FunctionInstance : AutoCloseable {
-    /**
-     * The state of the instance.
-     */
-    public val state: FunctionInstanceState
-
-    /**
-     * The [FunctionObject] that is represented by this instance.
-     */
-    public val function: FunctionObject
-
-    /**
-     * Invoke the function instance.
-     *
-     * This method will suspend execution util the function instance has returned.
-     */
-    public suspend fun invoke()
-
-    /**
-     * Indicate to the resource manager that the instance is not needed anymore and may be cleaned up by the resource
-     * manager.
-     */
-    public override fun close()
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstanceListener.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstanceListener.kt
deleted file mode 100644
index e88b7104..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstanceListener.kt
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.deployer
-
-/**
- * Listener interface for events originating from a [FunctionInstance].
- */
-public interface FunctionInstanceListener {
-    /**
-     * This method is invoked when the state of a [FunctionInstance] has changed.
-     */
-    public fun onStateChanged(
-        instance: FunctionInstance,
-        newState: FunctionInstanceState,
-    ) {}
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstanceState.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstanceState.kt
deleted file mode 100644
index 0c310e6b..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/deployer/FunctionInstanceState.kt
+++ /dev/null
@@ -1,48 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.deployer
-
-/**
- * This enumeration describes the states of a [FunctionInstance].
- */
-public enum class FunctionInstanceState {
-    /**
-     * The function instance is currently being provisioned.
-     */
-    Provisioning,
-
-    /**
-     * The function instance is idle and ready to execute.
-     */
-    Idle,
-
-    /**
-     * The function instance is executing.
-     */
-    Active,
-
-    /**
-     * The function instance is released and cannot be used anymore.
-     */
-    Deleted,
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/internal/FaaSFunctionImpl.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/internal/FaaSFunctionImpl.kt
deleted file mode 100644
index 7cc85e40..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/internal/FaaSFunctionImpl.kt
+++ /dev/null
@@ -1,70 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.internal
-
-import org.opendc.faas.api.FaaSFunction
-import org.opendc.faas.service.FunctionObject
-import java.util.UUID
-
-/**
- * A [FaaSFunction] implementation that is passed to clients.
- */
-internal class FaaSFunctionImpl(
-    private val service: FaaSServiceImpl,
-    private val state: FunctionObject,
-) : FaaSFunction {
-    override val uid: UUID = state.uid
-
-    override var name: String = state.name
-        private set
-
-    override var memorySize: Long = state.memorySize
-        private set
-
-    override var labels: Map<String, String> = state.labels.toMap()
-        private set
-
-    override var meta: Map<String, Any> = state.meta.toMap()
-        private set
-
-    override suspend fun delete() {
-        service.delete(state)
-    }
-
-    override suspend fun invoke() {
-        service.invoke(state)
-    }
-
-    override suspend fun refresh() {
-        name = state.name
-        memorySize = state.memorySize
-        labels = state.labels
-        meta = state.meta
-    }
-
-    override fun equals(other: Any?): Boolean = other is FaaSFunctionImpl && uid == other.uid
-
-    override fun hashCode(): Int = uid.hashCode()
-
-    override fun toString(): String = "FaaSFunction[uid=$uid,name=$name]"
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/internal/FaaSServiceImpl.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/internal/FaaSServiceImpl.kt
deleted file mode 100644
index 397b0e7d..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/internal/FaaSServiceImpl.kt
+++ /dev/null
@@ -1,290 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.internal
-
-import kotlinx.coroutines.InternalCoroutinesApi
-import kotlinx.coroutines.intrinsics.startCoroutineCancellable
-import kotlinx.coroutines.suspendCancellableCoroutine
-import mu.KotlinLogging
-import org.opendc.common.Dispatcher
-import org.opendc.common.util.Pacer
-import org.opendc.faas.api.FaaSClient
-import org.opendc.faas.api.FaaSFunction
-import org.opendc.faas.service.FaaSService
-import org.opendc.faas.service.FunctionObject
-import org.opendc.faas.service.autoscaler.FunctionTerminationPolicy
-import org.opendc.faas.service.deployer.FunctionDeployer
-import org.opendc.faas.service.deployer.FunctionInstance
-import org.opendc.faas.service.deployer.FunctionInstanceListener
-import org.opendc.faas.service.deployer.FunctionInstanceState
-import org.opendc.faas.service.router.RoutingPolicy
-import org.opendc.faas.service.telemetry.FunctionStats
-import org.opendc.faas.service.telemetry.SchedulerStats
-import java.lang.IllegalStateException
-import java.time.Duration
-import java.time.InstantSource
-import java.util.ArrayDeque
-import java.util.Random
-import java.util.UUID
-import kotlin.coroutines.Continuation
-import kotlin.coroutines.resumeWithException
-
-/**
- * Implementation of the [FaaSService] interface.
- *
- * This component acts as the function router from the SPEC RG Reference Architecture for FaaS and is responsible
- * for routing incoming requests or events to the correct [FunctionInstance]. If no [FunctionInstance] is available,
- * this component queues the events to await the deployment of new instances.
- */
-internal class FaaSServiceImpl(
-    dispatcher: Dispatcher,
-    private val deployer: FunctionDeployer,
-    private val routingPolicy: RoutingPolicy,
-    private val terminationPolicy: FunctionTerminationPolicy,
-    quantum: Duration,
-) : FaaSService, FunctionInstanceListener {
-    /**
-     * The logger instance of this server.
-     */
-    private val logger = KotlinLogging.logger {}
-
-    /**
-     * The [Pacer] to use for scheduling the scheduler cycles.
-     */
-    private val pacer = Pacer(dispatcher, quantum.toMillis()) { doSchedule() }
-
-    /**
-     * The [InstantSource] instance representing the clock.
-     */
-    private val clock = dispatcher.timeSource
-
-    /**
-     * The [Random] instance used to generate unique identifiers for the objects.
-     */
-    private val random = Random(0)
-
-    /**
-     * The registered functions for this service.
-     */
-    private val functions = mutableMapOf<UUID, FunctionObject>()
-    private val functionsByName = mutableMapOf<String, FunctionObject>()
-
-    /**
-     * The queue of invocation requests.
-     */
-    private val queue = ArrayDeque<InvocationRequest>()
-
-    /**
-     * Metrics tracked by the service.
-     */
-    private var totalInvocations = 0L
-    private var timelyInvocations = 0L
-    private var delayedInvocations = 0L
-
-    override fun newClient(): FaaSClient {
-        return object : FaaSClient {
-            private var isClosed: Boolean = false
-
-            /**
-             * Exposes a [FunctionObject] to a client-exposed [FaaSFunction] instance.
-             */
-            private fun FunctionObject.asClientFunction(): FaaSFunction {
-                return FaaSFunctionImpl(this@FaaSServiceImpl, this)
-            }
-
-            override suspend fun queryFunctions(): List<FaaSFunction> {
-                check(!isClosed) { "Client is already closed" }
-
-                return functions.values.map { it.asClientFunction() }
-            }
-
-            override suspend fun findFunction(id: UUID): FaaSFunction? {
-                check(!isClosed) { "Client is already closed" }
-
-                return functions[id]?.asClientFunction()
-            }
-
-            override suspend fun findFunction(name: String): FaaSFunction? {
-                check(!isClosed) { "Client is already closed" }
-
-                return functionsByName[name]?.asClientFunction()
-            }
-
-            override suspend fun newFunction(
-                name: String,
-                memorySize: Long,
-                labels: Map<String, String>,
-                meta: Map<String, Any>,
-            ): FaaSFunction {
-                check(!isClosed) { "Client is already closed" }
-                require(name !in functionsByName) { "Function with same name exists" }
-
-                val uid = UUID(clock.millis(), random.nextLong())
-                val function =
-                    FunctionObject(
-                        uid,
-                        name,
-                        memorySize,
-                        labels,
-                        meta,
-                    )
-
-                functionsByName[name] = function
-                functions[uid] = function
-
-                return function.asClientFunction()
-            }
-
-            override suspend fun invoke(name: String) {
-                check(!isClosed) { "Client is already closed" }
-
-                val func = requireNotNull(functionsByName[name]) { "Unknown function" }
-                this@FaaSServiceImpl.invoke(func)
-            }
-
-            override fun close() {
-                isClosed = true
-            }
-        }
-    }
-
-    override fun getSchedulerStats(): SchedulerStats {
-        return SchedulerStats(totalInvocations, timelyInvocations, delayedInvocations)
-    }
-
-    override fun getFunctionStats(function: FaaSFunction): FunctionStats {
-        val func = requireNotNull(functions[function.uid]) { "Unknown function" }
-        return func.getStats()
-    }
-
-    /**
-     * Indicate that a new scheduling cycle is needed due to a change to the service's state.
-     */
-    private fun schedule() {
-        // Bail out in case the queue is empty.
-        if (queue.isEmpty()) {
-            return
-        }
-
-        pacer.enqueue()
-    }
-
-    /**
-     * Run a single scheduling iteration.
-     */
-    @OptIn(InternalCoroutinesApi::class)
-    private fun doSchedule() {
-        try {
-            while (queue.isNotEmpty()) {
-                val (submitTime, function, cont) = queue.poll()
-
-                val instances = function.instances
-
-                // Check if there exists an instance of the function
-                val activeInstance =
-                    if (instances.isNotEmpty()) {
-                        routingPolicy.select(instances, function)
-                    } else {
-                        null
-                    }
-
-                val instance =
-                    if (activeInstance != null) {
-                        timelyInvocations++
-                        function.reportDeployment(isDelayed = false)
-
-                        activeInstance
-                    } else {
-                        val instance = deployer.deploy(function, this)
-                        instances.add(instance)
-                        terminationPolicy.enqueue(instance)
-
-                        delayedInvocations++
-                        function.reportDeployment(isDelayed = true)
-
-                        instance
-                    }
-
-                suspend {
-                    val start = clock.millis()
-                    function.reportStart(start, submitTime)
-                    try {
-                        instance.invoke()
-                    } catch (e: Throwable) {
-                        logger.debug(e) { "Function invocation failed" }
-                        function.reportFailure()
-                    } finally {
-                        val end = clock.millis()
-                        function.reportEnd(end - start)
-                    }
-                }.startCoroutineCancellable(cont)
-            }
-        } catch (cause: Throwable) {
-            logger.error(cause) { "Exception occurred during scheduling cycle" }
-        }
-    }
-
-    suspend fun invoke(function: FunctionObject) {
-        check(function.uid in functions) { "Function does not exist (anymore)" }
-
-        totalInvocations++
-        function.reportSubmission()
-
-        return suspendCancellableCoroutine { cont ->
-            if (!queue.add(InvocationRequest(clock.millis(), function, cont))) {
-                cont.resumeWithException(IllegalStateException("Failed to enqueue request"))
-            } else {
-                schedule()
-            }
-        }
-    }
-
-    fun delete(function: FunctionObject) {
-        functions.remove(function.uid)
-        functionsByName.remove(function.name)
-    }
-
-    override fun close() {
-        // Stop all function instances
-        for ((_, function) in functions) {
-            function.close()
-        }
-    }
-
-    override fun onStateChanged(
-        instance: FunctionInstance,
-        newState: FunctionInstanceState,
-    ) {
-        terminationPolicy.onStateChanged(instance, newState)
-
-        if (newState == FunctionInstanceState.Deleted) {
-            val function = instance.function
-            function.instances.remove(instance)
-        }
-    }
-
-    /**
-     * A request to invoke a function.
-     */
-    private data class InvocationRequest(val timestamp: Long, val function: FunctionObject, val cont: Continuation<Unit>)
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/router/RandomRoutingPolicy.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/router/RandomRoutingPolicy.kt
deleted file mode 100644
index 1eb03e5a..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/router/RandomRoutingPolicy.kt
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.router
-
-import org.opendc.faas.service.FunctionObject
-import org.opendc.faas.service.deployer.FunctionInstance
-import java.util.SplittableRandom
-import java.util.random.RandomGenerator
-
-/**
- * A [RoutingPolicy] that selects a random function instance.
- */
-public class RandomRoutingPolicy(private val random: RandomGenerator = SplittableRandom(0)) : RoutingPolicy {
-    override fun select(
-        instances: List<FunctionInstance>,
-        function: FunctionObject,
-    ): FunctionInstance {
-        val idx = random.nextInt(instances.size)
-        return instances.elementAt(idx)
-    }
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/router/RoutingPolicy.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/router/RoutingPolicy.kt
deleted file mode 100644
index c8ea37fc..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/router/RoutingPolicy.kt
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.router
-
-import org.opendc.faas.service.FunctionObject
-import org.opendc.faas.service.deployer.FunctionInstance
-
-/**
- * A [RoutingPolicy] decides to which [FunctionInstance] a function invocation should be routed.
- */
-public interface RoutingPolicy {
-    /**
-     * Select the instance to which the request should be routed to.
-     */
-    public fun select(
-        instances: List<FunctionInstance>,
-        function: FunctionObject,
-    ): FunctionInstance?
-}
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/telemetry/FunctionStats.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/telemetry/FunctionStats.kt
deleted file mode 100644
index db6db6c1..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/telemetry/FunctionStats.kt
+++ /dev/null
@@ -1,48 +0,0 @@
-/*
- * Copyright (c) 2022 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.telemetry
-
-import org.apache.commons.math3.stat.descriptive.DescriptiveStatistics
-
-/**
- * Statistics about function invocations.
- *
- * @property totalInvocations The number of function invocations.
- * @property timelyInvocations The number of function invocations that could be handled directly.
- * @property delayedInvocations The number of function invocations that are delayed (cold starts).
- * @property failedInvocations The number of function invocations that failed.
- * @property activeInstances The number of active function instances.
- * @property idleInstances The number of idle function instances.
- * @property waitTime Statistics about the wait time of a function invocation.
- * @property activeTime Statistics about the runtime of a function invocation.
- */
-public data class FunctionStats(
-    val totalInvocations: Long,
-    val timelyInvocations: Long,
-    val delayedInvocations: Long,
-    val failedInvocations: Long,
-    val activeInstances: Int,
-    val idleInstances: Int,
-    val waitTime: DescriptiveStatistics,
-    val activeTime: DescriptiveStatistics,
-)
diff --git a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/telemetry/SchedulerStats.kt b/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/telemetry/SchedulerStats.kt
deleted file mode 100644
index b65dfb03..00000000
--- a/opendc-faas/opendc-faas-service/src/main/kotlin/org/opendc/faas/service/telemetry/SchedulerStats.kt
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * Copyright (c) 2022 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service.telemetry
-
-/**
- * Statistics reported by the FaaS scheduler.
- *
- * @property totalInvocations The total amount of function invocations received by the scheduler.
- * @property timelyInvocations The amount of function invocations that could be handled directly.
- * @property delayedInvocations The amount of function invocations that were delayed due to function deployment.
- */
-public data class SchedulerStats(
-    val totalInvocations: Long,
-    val timelyInvocations: Long,
-    val delayedInvocations: Long,
-)
diff --git a/opendc-faas/opendc-faas-service/src/test/kotlin/org/opendc/faas/service/FaaSServiceTest.kt b/opendc-faas/opendc-faas-service/src/test/kotlin/org/opendc/faas/service/FaaSServiceTest.kt
deleted file mode 100644
index 72a5f2c8..00000000
--- a/opendc-faas/opendc-faas-service/src/test/kotlin/org/opendc/faas/service/FaaSServiceTest.kt
+++ /dev/null
@@ -1,185 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.faas.service
-
-import io.mockk.every
-import io.mockk.mockk
-import org.junit.jupiter.api.Assertions.assertEquals
-import org.junit.jupiter.api.Assertions.assertNotNull
-import org.junit.jupiter.api.Assertions.assertNull
-import org.junit.jupiter.api.Test
-import org.junit.jupiter.api.assertDoesNotThrow
-import org.junit.jupiter.api.assertThrows
-import org.opendc.faas.api.FaaSFunction
-import org.opendc.faas.service.deployer.FunctionDeployer
-import org.opendc.faas.service.deployer.FunctionInstance
-import org.opendc.faas.service.deployer.FunctionInstanceState
-import org.opendc.simulator.kotlin.runSimulation
-import java.util.UUID
-
-/**
- * Test suite for the [FaaSService] implementation.
- */
-internal class FaaSServiceTest {
-    @Test
-    fun testClientState() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = assertDoesNotThrow { service.newClient() }
-            assertDoesNotThrow { client.close() }
-
-            assertThrows<IllegalStateException> { client.queryFunctions() }
-            assertThrows<IllegalStateException> { client.newFunction("test", 128) }
-            assertThrows<IllegalStateException> { client.invoke("test") }
-            assertThrows<IllegalStateException> { client.findFunction(UUID.randomUUID()) }
-            assertThrows<IllegalStateException> { client.findFunction("name") }
-        }
-
-    @Test
-    fun testClientInvokeUnknown() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-
-            assertThrows<IllegalArgumentException> { client.invoke("test") }
-        }
-
-    @Test
-    fun testClientFunctionCreation() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-
-            val function = client.newFunction("test", 128)
-
-            assertEquals("test", function.name)
-        }
-
-    @Test
-    fun testClientFunctionQuery() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-
-            assertEquals(emptyList<FaaSFunction>(), client.queryFunctions())
-
-            val function = client.newFunction("test", 128)
-
-            assertEquals(listOf(function), client.queryFunctions())
-        }
-
-    @Test
-    fun testClientFunctionFindById() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-
-            assertEquals(emptyList<FaaSFunction>(), client.queryFunctions())
-
-            val function = client.newFunction("test", 128)
-
-            assertNotNull(client.findFunction(function.uid))
-        }
-
-    @Test
-    fun testClientFunctionFindByName() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-
-            assertEquals(emptyList<FaaSFunction>(), client.queryFunctions())
-
-            val function = client.newFunction("test", 128)
-
-            assertNotNull(client.findFunction(function.name))
-        }
-
-    @Test
-    fun testClientFunctionDuplicateName() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-
-            client.newFunction("test", 128)
-
-            assertThrows<IllegalArgumentException> { client.newFunction("test", 128) }
-        }
-
-    @Test
-    fun testClientFunctionDelete() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-            val function = client.newFunction("test", 128)
-            assertNotNull(client.findFunction(function.uid))
-            function.delete()
-            assertNull(client.findFunction(function.uid))
-
-            // Delete should be idempotent
-            function.delete()
-        }
-
-    @Test
-    fun testClientFunctionCannotInvokeDeleted() =
-        runSimulation {
-            val service = FaaSService(dispatcher, mockk(), mockk(), mockk())
-
-            val client = service.newClient()
-            val function = client.newFunction("test", 128)
-            assertNotNull(client.findFunction(function.uid))
-            function.delete()
-
-            assertThrows<IllegalStateException> { function.invoke() }
-        }
-
-    @Test
-    fun testClientFunctionInvoke() =
-        runSimulation {
-            val deployer = mockk<FunctionDeployer>()
-            val service = FaaSService(dispatcher, deployer, mockk(), mockk(relaxUnitFun = true))
-
-            every { deployer.deploy(any(), any()) } answers {
-                object : FunctionInstance {
-                    override val state: FunctionInstanceState = FunctionInstanceState.Idle
-                    override val function: FunctionObject = it.invocation.args[0] as FunctionObject
-
-                    override suspend fun invoke() {}
-
-                    override fun close() {}
-                }
-            }
-
-            val client = service.newClient()
-            val function = client.newFunction("test", 128)
-
-            function.invoke()
-        }
-}